The invention discloses a method and an apparatus of determining geometrical dimensions of a motor vehicle wheel; in particular, the invention discloses a method and an apparatus of determining geometrical dimensions of a motor vehicle wheel (rim/tyre assembly) (1) by contact-less sensing, wherein the wheel is fixed on wheel receiving means (2) of a tyre changer, that at least one light beam (21)is emitted on to the wheel or at least a part of the wheel, wherein the light beam reflected at the impingement area is detected, and wherein the directions of the emitted and reflected light beams are evaluated for determining the shape and/or position of the respective impingement area on the wheel.